Alarm for motion-picture-film reels



M. F. WALKER.

ALARM FOR MOTION PICTURE FILM REELS.

APPLICATION FILED SEPT. 25, I9I8.

Patented Aug. 3, 1920.

me/whoa Mosns r. wALKER,f-or CADIZ, OHIO; y

ALARM: FOR no rron-rrcfrunnrrmvr linens..

asiatica.

Original application led March 1,4, 1,918, Serial No. 222,436. Dividedand this application led Septem- 1 ber `25, 191s. serial No. 255,718; rv

To all 'whom t may concern,

Be it known that I, Moens F. WALKER, a citizen of the United States,residing at Cadiz,'in the county of Harrison and tate of Ohio, haveinvented certain newand useful Improvements in Alarms for Motion-Picture-Film Reels, of which vthe following is a specification.

This invention relatesto motion picture film reels. v

ln the exhibition of motion'pictures it is customary kto employ twoprojecting machines so that one machine being in opera-v tion to projectthe motion pictures, and the endV of the film passingtherethrough havingbeen reached, the operator may immediately commence the operation of.the second ma'- chine so as to avoid interruption or delay in the'exhibition of the pictures. and iny this manner the two machines may bealternately operated so as to reproduce, for example`,a`1i entireplaywithout linterruption which would otherwisebe necessary in order topermit lof removal lofV the'magazinereel and the placing in position' ofthe newy reel and the threading of the film-through the machine.In'orderfthattwo machines may be successfully employed in'this manner,however, it is, of course, essential that the operator know when the endof the lmbeing eX- hibited has been substantially reached. All

'though the practice is discouragedjand in some cases prohibited/anoperator will ordinarily Open'the door ofthe fire-proofmagazine, fromtime to time in order to `ascertain the length of film remaining .on themagazine or supply reel. Not only is this .practice'exceedinglydangerous as the heat from `the arc of the projecting machine is liableto set fire to the film,.but furthermore, ,the operators attention is,toa greater or less eX- tent, detracted from the operation of themachine and he is liablev to operate the same either too rapidly or tooslowly. fItlisnthere'- fore, one aim of thepresent invention to provide,in connection with a lm reel of the classV described, means ywhich will`give audible signal when Vall but a predetermined length of the lmhasbeen unwound from the reel, so that with a ylittlepracticey theoperator, in the use of the device, may `determine almost exactly thenumber nofturns to give the operating crank 'of the project? ingapparatus after hearing the signal and before beginningtoturn the crankofthe ,'Ehis ,application constitutes a second -machinef .Therefore notonly does l l the invention discourage` the dangerous practice ofyopening. the door ofthe maga- Zine, but it alsopresents obviousadvantages over certain devices which havel been proposed for use andwhich embody visible indi eating means whereby the length. of film uponthe ysupply. reel maybe determined,

for in the use of such devices the operator must pay more or less closeyattentionto the indicator. v" V Anotherk aimof the inventionis toprovide an audible alarm for the purpose above described which will beAso constructed that the operator` of the machine may set the same togive signal when allbut any desired length'of the filmhas been unwoundfrom'the reel.` ln other words,-the"invention may be made use of by anoperator who ydesires rto `be lwarned: when therev is, for i eX- ample,only a 'foot ofiihn leftjupon the mag'- azine or supply reel, asequallyV as vwellfasit maybe employed by an'` operator who desires 'tobe warnedwhenrthere are'thre'e or four feet, for eXam'ple,pof film`remaining upon Vthe reel.

In order thata device oflvthis class may be most certainand accurate' initsk functioning, it is, ofcourse, 'essentialfthat its. actuation ybecontrolled by the unwinding ofthe film and the present invention,therefore, aims to y so construct the device thatl although itypossesses this advantage,it `will not :be in any manner likely toinjure. the film or yplace any unduetensionthereon. f 7 f f division ofmyl application filed `March 14, 1918, Serial No.292,456.y .i

In the accompanying drawings k Figure l is 'a view in side elevation ofthe film'reel embodying the present invention; j

Fig. 2 is avertical Vsectionalviewfon the line '2 2 of Fig. 1;

, Fig-3 is a vertical'sectional V.view taken substantially on the lineV3-3 ofvFig. 2 looking in the Ldirection indicated by the arrow.; LF-ig.iis a detail viewl in elevation looking .at-the lcentral portionyof ronehead vof the reel Q Fig.k 5 is a'perspective view of an. element ofthealarm device.` j

In the drawings the heads of thereeliare indicated in' general by thenumeral l and the yhubis indicated in general by the numeralfQ.. ,f Thesaid hub is preferably formed thepbody 3 and at their outer ends arepro-V vided with tongues 5 which are fitted throughV slots (5` :formedin one head of the reel and struck down, as shown in Fig. 1 ofY thedrawings. The other head of the reel is removably secured in place bylmeans of bolts 7 which are fitted through registering openings formedin the said head of the reel and the said head 3 of the hub,the boltspassing ,also through openings in the other head ofthe reel and havingapplied. thereto nuts 8 which bear against the outer face of thelast-mentioned head of the reel. rllhe last mentioned head of the reelis Vindicated specificallyby `the numeral 1a and the other head by thenumeral 1b. L

The spindle bearing for the reel comprises asleeve 9 which vatonev endis fittedthrough an opening formed in the head 11L and is riveted down,as clearly shownin Fig. 2 of the drawings.V The other endof the sleeve),however, is'not riveted, and slidably fitted onto the sleeve is a secondsleeve 10 which at one end is reduced and squared as indicated by thenumeral 11so as to fit `within a correspondingly shaped opening 12-formed axially in the head 1b of the reel. Exteriorly the sleeve 10 isthreaded at its opposite end, as indicated by the numeral 13, and ttedonto this end of the sleeve is a bell 14. For coaction with the bell'14there is provided a striker comprising a: head 15 'which is fixed at oneend of' a resilient wire shank 16, which shank near the said end `isbent to provide a linger 17 and beyond the finger the said wire iscoiled as at 18 to give the increased resili# ency. The other end of thewire shank is secured as at 19to the head 1a of' the reel and theresiliency of the shank is such that when the finger 17 is pulled ormoved in the direction of the head1a and released, the striker `head 15will be caused to strike the bell 14. Pivotally mounted as at 20 uponthehead 1a is a detent member indicated in general by thenumeral 21 andincluding a film engaging arm 22 and a lip 23,`the arm and lip lying atopposite sides of the pivot 2O andthe arm being designed to extendacross the film and consequently across the hub of the reel. The lip'23, however, extends in the path of movement of the finger 17 so as tobe engaged by the said finger when the signal device is set foractuationin a manner which will now be explained.

In setting the device, a predetermined length of film is first woundupon the reel and the arm 22 is then placed over the film and thewinding ofthe Hlm is completed.

Finally the finger 17 is grasped and placed in engagement with the lip23 and the reel is then ready to be placed in the magazine. As the lm isVunwound from the reel and as that portion inthe length thereof whichextends over the arm 22 leaves the hub,the arm 22 ,will be released andthe detent member as a whole will be swung under the infiuence of theresilient shank 16 thereby permitting the finger 17 todisengagefrom'thelip 23 and the striker `head 15 to strike the bell 14and -give audible signal to the operator of' the pro- .any predeterminednumber of films remaining upon the reel to be unwound and in fact, ifdesired, two of the-.devices may be placed upon the same reel so thatone device will Vserve to warn the operator to close the electriccircuit throughthe arcV lamp ofthe second machine to permit' of theformation of the crater and-therefore provide against interruption ofthe projection of the light rays. This particular alarm would, ofcourse, sound some time before sounding ofl the other alarm for thepurpose stated.

*Having thus described the inventiomwhat is claimed as new'is:

1. In a film reel, a bell carried by said reel, a `striker element forcoaction therewith, and means for. actuating the striker element, thestriker element being arranged to be actuated automatically when allbuta predetermined length of the lilm has been unwound from the reel. l 4

2. The combination witha film reel, of a vsounding element carriedthereby, a striking element normally tending to c'oact with theisoundingelement, and a filml released detent for the striking elementactuated when all but a Vpredetermined length of lm has been unwound. vA

3. The combinationwith a ilmrecl, of a `sounding element carriedthereby, a `striking element normally tending toy co-act with thesounding element, and a detent for the striking elementincluding aportion `to be engagedby the lm wound upon the reel untilsuchtime as allbut ya predeten mined length of lmV has been unwound.

` 4. The combination in afilm reel, of a bell carried thereby,and astriker normally urged toward thebell, and a film released detent ex*tending between the convolutions of the film tobe released when all buta predetermined length of film is unwound to permit actuation of saidstriker.`

" 5. The combination in a film reel, of a bell carried on the hubthereof, a striker nor-v a striker, and a lilm released detentextendmally urged toward the bell, and a lilm reing between theConvolutions of the ilm `to 10 leased detent extending between theconvolube released when all but a predetermined tions of the ilmto bereleased when all but length of film is unwound to permit actua- 5 apredetermined length of lm is unwound tion of said striker.l

to permit actuation of said striker. In testimony whereof I afliX mysignature.

6. The combination in a film reel having heads, a bell mountedintermediate the heads, MOSES F. WALKER. [1.. S.]

